tuna: add support for battery LED charging

Device has multi-color RGB LED, enable charging function
using existing custom lights library.

1 files changed, 85 insertions, 29 deletions

diff --git a/liblight/lights.c b/liblight/lights.c
index 1dfcd8b..e155d70 100644
--- a/liblight/lights.c
+++ b/liblight/lights.c
@@ -35,16 +35,27 @@ char const *const LED_FILE = "/dev/an30259a_leds";
 #define IMAX 0 // 12.75mA power consumption
 
 // Slope values, based on total blink of 1000ms
-#define SLOPE_UP_1		450
-#define SLOPE_UP_2		(500-SLOPE_UP_1)
+#define SLOPE_UP_1	450
+#define SLOPE_UP_2	(500-SLOPE_UP_1)
 #define SLOPE_DOWN_1	SLOPE_UP_2
 #define SLOPE_DOWN_2	SLOPE_UP_1
 // brightness at mid-slope, on 0 - 127 scale
 #define MID_BRIGHTNESS  31
 
+enum LED_Type {
+	LED_TYPE_ATTENTION = 0,
+	LED_TYPE_NOTIFICATION = 1,
+	LED_TYPE_CHARGING = 2,
+	LED_TYPE_LAST = 3
+};
+
+// a "stack" of virtual LED states
+static struct an30259a_pr_control g_led_states[LED_TYPE_LAST];
+
 void init_g_lock(void)
 {
 	pthread_mutex_init(&g_lock, NULL);
+	memset(g_led_states, 0, sizeof(g_led_states));
 }
 
 static int write_int(char const *path, int value)
@@ -132,48 +143,91 @@ static int write_leds(struct an30259a_pr_control *led)
 	return err;
 }
 
+// similar to write_leds(), but deals with the priority of certain virtual LEDs over others
+static int write_leds_priority()
+{
+	// find the highest priority virtual LED that should be illuminated and
+	// call write_leds() with it
+	int i;
+
+	for (i = 0; i < LED_TYPE_LAST; i++) {
+		// if the LED isn't off and isn't "black" then use it
+		if (g_led_states[i].state != LED_LIGHT_OFF) {
+			return write_leds(&g_led_states[i]);
+		}
+	}
+
+	// nothing should be lit?  make sure to turn it off
+	return write_leds(&g_led_states[LED_TYPE_LAST - 1]);
+}
+
 static int set_light_leds(struct light_state_t const *state, int type)
 {
-	struct an30259a_pr_control led;
-
-	memset(&led, 0, sizeof(led));
-
-	switch (state->flashMode) {
-	case LIGHT_FLASH_NONE:
-		led.state = LED_LIGHT_OFF;
-		break;
-	case LIGHT_FLASH_TIMED:
-	case LIGHT_FLASH_HARDWARE:
-		led.state = LED_LIGHT_SLOPE;
-		led.color = state->color & 0x00ffffff;
-		// tweak to eliminate purplish tint from white color
-		if (led.color == 0x00ffffff)
-		    led.color = 0x80ff80;
-		// scale slope times based on flashOnMS
-		led.time_slope_up_1 = (SLOPE_UP_1 * state->flashOnMS) / 1000;
-		led.time_slope_up_2 = (SLOPE_UP_2 * state->flashOnMS) / 1000;
-		led.time_slope_down_1 = (SLOPE_DOWN_1 * state->flashOnMS) / 1000;
-		led.time_slope_down_2 = (SLOPE_DOWN_2 * state->flashOnMS) / 1000;
-		led.mid_brightness = MID_BRIGHTNESS;
-		led.time_off = state->flashOffMS;
-		break;
-	default:
+	if (type < 0 || type >= LED_TYPE_LAST) {
 		return -EINVAL;
 	}
 
-	return write_leds(&led);
+	struct an30259a_pr_control *led_state = &g_led_states[type];
+
+	// set the LED information to the proper element of the array without actually
+	// changing the physical LED yet
+	memset(led_state, 0, sizeof(*led_state));
+
+	// if the color is 0, turn off the LED
+	if (state->color & 0xffffff) {
+		led_state->color = state->color & 0x00ffffff;
+		// tweak to eliminate purplish tint from white color
+		if (led_state->color == 0x00ffffff) {
+			led_state->color = 0x80ff80;
+		}
+
+		switch (state->flashMode) {
+		case LIGHT_FLASH_NONE:
+			led_state->state = LED_LIGHT_ON;
+			break;
+		case LIGHT_FLASH_TIMED:
+		case LIGHT_FLASH_HARDWARE:
+			led_state->state = LED_LIGHT_SLOPE;
+			// scale slope times based on flashOnMS
+			led_state->time_slope_up_1 = (SLOPE_UP_1 * state->flashOnMS) / 1000;
+			led_state->time_slope_up_2 = (SLOPE_UP_2 * state->flashOnMS) / 1000;
+			led_state->time_slope_down_1 = (SLOPE_DOWN_1 * state->flashOnMS) / 1000;
+			led_state->time_slope_down_2 = (SLOPE_DOWN_2 * state->flashOnMS) / 1000;
+			led_state->mid_brightness = MID_BRIGHTNESS;
+			led_state->time_off = state->flashOffMS;
+			break;
+		default:
+			return -EINVAL;
+		}
+	} else {
+		led_state->state = LED_LIGHT_OFF;
+	}
+
+	// allow write_leds_priority determine if the physical LED should be changed
+	return write_leds_priority();
 }
 
 static int set_light_leds_notifications(struct light_device_t *dev,
 			struct light_state_t const *state)
 {
-	return set_light_leds(state, 0);
+	return set_light_leds(state, LED_TYPE_NOTIFICATION);
 }
 
 static int set_light_leds_attention(struct light_device_t *dev,
 			struct light_state_t const *state)
 {
-	return set_light_leds(state, 1);
+	struct light_state_t attention_state = *state;
+	if (attention_state.flashMode == LIGHT_FLASH_NONE) {
+	    // that's actually NotificationManager's way of turning it off
+	    attention_state.color = 0;
+	}
+	return set_light_leds(&attention_state, LED_TYPE_ATTENTION);
+}
+
+static int set_light_leds_battery(struct light_device_t *dev,
+			struct light_state_t const *state)
+{
+	return set_light_leds(state, LED_TYPE_CHARGING);
 }
 
 static int open_lights(const struct hw_module_t *module, char const *name,
@@ -188,6 +242,8 @@ static int open_lights(const struct hw_module_t *module, char const *name,
 		set_light = set_light_leds_notifications;
 	else if (0 == strcmp(LIGHT_ID_ATTENTION, name))
 		set_light = set_light_leds_attention;
+	else if (0 == strcmp(LIGHT_ID_BATTERY, name))
+		set_light = set_light_leds_battery;
 	else
 		return -EINVAL;